differentiate x^3y three times with respect to x
1) Let's differentiate: ddx(x3y)
ⓘ For differentiation with respect to x, y is treated as constant. A constant factor stays in front of the derivative, (k*u)' = k*u': ddx(x3y) = y·ddx(x3)■The derivative of x^n is n*x^(n-1): ddx(x3) = 3x2
y·3x2
2) Let's perform the differentiation: ddx(3x2y)
ⓘ For differentiation with respect to x, 3y is treated as constant. A constant factor stays in front of the derivative, (k*u)' = k*u': ddx(3x2y) = 3y·ddx(x2)
3y·ddx(x2)
ⓘ The derivative of x^n is n*x^(n-1): ddx(x2) = 2x
3y·2x
ⅰ 3·2 = 6
6yx
3) Let's perform the differentiation: ddx(6xy)
ⓘ For differentiation with respect to x, 6y is treated as constant. A constant factor stays in front of the derivative, (k*u)' = k*u': ddx(6xy) = 6y·ddx(x)
6y·ddx(x)
ⓘ The derivative of x is 1: ddx(x) = 1
6y·1
▶Derivative:   6y